Inductor mounting means for an induction furnace



Nov. 11, 19 69 J. M. LARKIN 3,473,157

INDUCTOR MOUNTING MEANS FOR AN INDUCTION FURNACE Filed Nov. 20, 1967 2 Sheets-Sheet l 22 l O 24 xix/" o 25 O fi l 2 7 2| I II 5 |2 INVENTOR J. M. LARKIN Nov. 11, 1969 INDUCTOR MOUNTING MEANS FOR AN INDUCTION FURNACE Filed Nov. 20, 1967 2 Sheets-Sheet 2 INVENTOR United States Patent 3,478,157 INDUCTOR MOUNTING MEANS FOR AN INDUCTION FURNACE John M. Larkin, Evergreen Park, Ill., assignor to Whiting Corporation, a corporation of Illinois Filed Nov. 20, 1967, Ser. No. 684,393 Int. Cl. H05b 5/14 U.S. CI. 1329 2 Claims ABSTRACT OF THE DISCLOSURE The inductor assembly which is mounted to the furnace shell exteriorly thereof includes a continuous flange in confronting spaced relation with a flange on the shell. A continuous ring assembly includes a plurality of sections each of channel shaped cross-section with the flanges of the latter in coextensive contact with the flanges on the shell and housing, respectively. The ring assembly may be completely removed thereby exposing the continuous refractory formation which is fused with the refractory lining in the shell and with the refractory material in the inductor housing, whereby such refractory formation is accessible for sawing or chipping to remove the inductor assembly for repair or replacement.

Objects of the invention A primary object of the present invention is to provide new and improved means for mounting an inductor to an induction furnace of the type having submerged inductors.

Another object of the present invention is the provision of new and improved means for mounting an inductor in a furnace of the type described, wherein such means permits ready removal of the inductor for repair or replacement without damaging the adjacent refractory lining in the furnace shell.

Still another object of the present invention is the provision of new and improved inductor mounting means of the type described, such mounting means including a mounting ring which may be readily removed thereby exposing the refractory formation which is fused to the refractory lining in the furnace shell and to the refractory material in the inductor.

'Another object of the present invention is the provision of inductor mounting means of the type described where- Description of the drawings FIG. 1 is a transverse'section taken through a horizontally disposed induction furnace of the type having submerged inductors; g

FIG. 2 is a fragmentary, enlarged section taken along line 2-2 of FIG. 1; and

FIG. 3 is a sectiontakenalong line 3- 3 of FIG. .2.

Description of a preferred embodiment Referring to FIG. 1, an induction furnace, generally designated 10, of the type having submerged inductors will be seen to include a horizontally disposed, cylindrical shell 12 of metal fabricated construction. The shell includes a pair of mounting rings 14 adjacent respective opposite ends thereof, which rings are received in roller Hce assemblies (not shown) thereby mounting the shell for rotation about a horizontal axis 15, such axis being eccentric with respect to the longitudinal central axis 16 of the shell. The shell has a lining consisting of cast-in-place refractory material 17, 18 and refractory bricks 19.

The furnace 10 includes a charging door opening defined by an opening 20 in the shell 12 and by an opening 21 in the refractory material 17. The charging door opening is covered by a charging door 22 mounted by one or more arms 24, each arm 24 being pivotally mounted about a pin 25 and connected with a hydraulic ram 26 for powered opening and closing of the charging door. A slag trough 28 is mounted on the furnace adjacent one edge of the charging door opening.

It-will be understood the furnace 10 includes the usual spouts. adjacent respective opposite ends thereof. It will also be understood the furnace is normally disposed as indicated in FIG. 1 and contains a charge of molten material, to .a level indicated by the line 29. The induction furnace 10 includes a plurality of electric inductor assemblies 30, preferably two or four, depending on whether the furnace is used as a melter or as a holder. It will be understood the furnace may be rotated about the axis 15 for elevating any one of the inductor assemblies 30 above the level of molten material for repair or replacement in a manner to be explained fully hereinbelow. The construction of the furnace and its mode of operation will not be described in detail herein as such construction and operation are well known to those skilled in the art;

Referring to FIGS. .2 and 3, the construction for mounting one of the inductor assemblies 30 to the furnace 10 will now be described. It will be understood that identical construction is used to mount the other inductor assemblies. The shell 12 includes an oval-shaped opening formed by a wall 31 and an integral flange 32 having a face 32a contained in a plane 33 perpendicular to a radius of the shell 12. The refractory material 18 extends into the aforedescribed opening in the shell 12, such refractory material including an opening 34 communicating with the chamber in the shell which contains the molten material.

The inductor assembly 30 consists of a metal housing 36 having a continuous flange 37 with a planar face 37a contained in a plane 38, such plane also being perpendicular to a radius of the shell 12. The housing 36 includes a refractory lining 40 and refractory sections 41, 42 mounting respective refractory insert blocks 43, 44; these refractory materials define a W-shaped passageway including a central portion 46 and outer portions 47 and 48, all of which portions communicate with the opening 34 in the refractory material 18. In FIG. 2, these passageways are shown as defined by metal shells 50, 51 and 52. Such shells are used to cast the refractory sections 40-42 in the shapes illustrated. However, as soon as the inductor is put into use, the molten material quickly melts these metal linings away thereby placing the molten material in direct contact with the refractory material. The inductor assembly 30 includes a pair of electric coils 53, 53a for heating the molten material which circulates from the chamber within the shell 12, through the opening 34 and through the various passageways 46-48.

The means for mounting the inductor assembly 30 to the shell 12 of the induction furnace consists of a pair of ring sections 54 and 55, which sections are of identical -construction. The ring section 54 includes upper and lower flanges 56 and 57 The ring sections 55 also includes such upper and lower flanges, the upper flange 58 being visible in FIG. 3. The ring section 54 contains outwardly extending web plates 59 at each of its ends adapted for abutting engagement with corresponding web plates 60 on the ring section 55. These web plates include suitable apertures receiving fasteners 61 for connecting the sections 54, 55 together to form a continuous ring.

The upper flanges of the ring sections 54, 55 are secured to the flange 32 on the shell 12 by a set of fasteners 63. Similarly, the lower flanges on the ring sections 54, 55 'are connected to the flange 37 on the inductor housing by another set of fasteners 64. All of these flanges are of course suitably apertured to receive the various fasteners.

When it is desired to remove one of the inductor assemblies 30 for repair or replacement, the furnace shell 12 is rotated for elevating the selected inductor assembly above the level of molten material in the furnace. The various electrical conductors and water hoses (not shown) extending to the inductor assembly will of course be disconnected. The fasteners 61, 63 and 64 are then removed permitting ready separation of the ring sections 54, 55. It will be understood that heat within the furnace will have fused the refractory material 18 to the refractory material 40 in the inductor assembly. Removal of the ring sections 54, 55 as aforesaid exposes the continuous refractory formation 65, which formation may be defined as that portion of the refractory material disposed between the planes 33, 38. This refractory formation is quite accessible and may be readily cut or chipped along the planes 33, 38, or along any plane therebetween, thereby permitting removal of the inductor assembly 30.

When the inductor assembly 30 is replaced, the refractory material will quickly be fused together along the parting plane which was formed to separate the refractory material 40 from the refractory material If chipping was used to separate these refractory materials, and if in the course of the chipping operation considerable refractory material was chipped away at the parting plane, additional refractory material may be inserted at the parting plane when the inductor assembly 30 is reinstalled. When removing the inductor assembly 30, it is preferable to saw the refractory material 18 along the plane 33 and the refractory material 40 along the plane 38. Then, a new and continuous refractory ring, which actually corresponds to the refractory portion 65 mentioned above, is inserted prior to bolting the ring sections 54, 55 to each other and to the respective flanges on the shell 12 and housing 36. The heat within the furnace will soon fuse these refractory sections together to form a homogenous refractory lining including the material 18 and the material 40.

Heretofore, it has not been possible to gain access to the refractory material prior to removal of the inductor assembly 30. In prior induction furnaces of which I am aware, the inductor housings have been directly bolted to the furnace shell or bolted to such shell by a continuous ring member. In such installations, removal of the fasteners between the inductor housing and the furnace shell would not of course permit separation of the inductor assembly because of the fused-together refractory material, and removal of such fasteners would not permit access to the refractory material itself. In these situations, it has been necessary to pry or force the inductor assembly from the furnace shell and in most cases this results in shattering of the refractory material 18 within the shell 12. The shattering of the refractory material made it quite diflicult to form a good bond or joint between the refractory lining in the shell and the refractory material in the re-installed or replacement inductor assembly. In some instances the shattering of the refractory material in the shell progressed to such an extent that it became necessary to shut the induction furnace down for repairs. Obviously, this is an expensive operation (furnaces of this type have a capacity of as much as 137 tons) and quite time consuming, as considerable time is required to allow the furnace to cool sufliciently for repair of the refractory material, and even more time, two weeks in some instances, is necessary to bring the furnace back up to its operating temperature.

Accordingly, it will be appreciated the present invention provides new and improved means for mounting an inductor assembly to the shell of an induction furnace in a manner that permits ready and expeditious removal of the inductor assembly for rep'air or replacement. The inductor assembly can be repaired or replaced without damaging the shell lining and the exposure to heat of the work-men engaged in such repair or replacement work is held to a minimum.

While the invention has been shown in but one form, it will be obvious to those skilled in the art it is not to be so limited. On the contrary, the invention is susceptible of various forms and modifications without departing from the spirit and scope of the appended claims.

I claim:

1. In an induction furnace of the type having one or more submerged inductors, wherein the furnace includes a generally cylindrical metal shell having a lining of refractory material defining a chamber for containing molten material, each inductor being mounted to said shell'exteriorly thereof adjacent an opening in the shell and in the adjoining refractory lining, such opening having their centers on a radius of the cylindrical shell, said inductor assembly including a metal housing having refractory material therein defining passageways communicating with said chambers, which assembly also includes electric heating means in the vicinity of said passagew 'ays for heating the material which flows therethrough, wherein a portion of the refractory material in said inductor assembly is fused with the adjacent refractory lining in said shell thereby forming a substantially homogenous refractory formation at the juncture of said assembly with said shell, which formation extends as a continuous band around said radius in a plane generally perpendicular thereto, the improvement comprising, me'ans for mounting said inductor housing to said shell, said mounting means including a continuous ring assembly interposed between said shell and said housing and contained in a plane generally perpendicular to said radius, fastening means detachably securing said ring assembly to said shell and to said housing, said ring assembly having a plurality of separable joints along the length thereof adapting the ring assembly to be detached from said furnace in sections independently of said inductor housing thereby exposing said refractory formation.

2. The improvement according to claim 1 further defined by, the opening in said shell being defined by a continuous flange contained in a plane generally perpendicular to said radius, said housing having a continuous flange in confronting spaced relation with the first mentioned flange, said ring assembly including a plurality of sections each of channel-shaped cross-section with the flanges of the latter in coextensive contact with said flanges on said shell and said housing, respectively.

References Cited UNITED STATES PATENTS 8/1963 Rydinger et al. 13-26 1/1968 Beckius et al 1329 US. Cl. XJR. 13-27 mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,478,157 Dated November 11, 1969 Inventor(s) John M. Larkin It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

8 Column 3, line 32, cancel "1f" and insert l o swam AND SEALED JUN 9 1970 6 m Attest:

WILLIAM E. 'SOHUYLER, JR.

Atwgting Officer 

